This invention relates to mounting systems and more particularly to shock mounting systems for isolating a payload support from a base support.
Fragile equipment generally requires protection against severe impacts, vibrations and other shocks. The problem is particularly acute during shipping.
Special shipping containers have been designed which include a payload support for supporting the fragile equipment, a base support which generally forms the lower portion of the shipping container, and isolators for affixing the payload support to the base support.
The loads imparted to the payload on the payload support are a function of the system natural frequency. The system natural frequency can be expressed as follows:
f = 1/2.pi..sqroot.k/m,
where
K = THE SPRING CONSTANT (POUNDS/INCH) AND
M = THE SPRING SUPPORTED MASS (POUNDS SEC.sup.2 /IN)
Thus, as the frequency increases, so do the forces to the payload. Also, as k/m increases, so do the forces imparted to the payload. Any increase or decrease in mass of the isolation supported mass must be accompanied by a proportional increase or decrease in the spring constant to maintain the forces imparted to the payload at a constant level.
Generally the isolation system for shipping containers is specifically designed for the mass of the particular payload which is being shipped. Accordingly, the spring constants of the isolators are selected according to the mass of the payload which is to be shipped in the container and another container must be designed for a payload with a different mass.